1. Field of the Invention
This invention relates to an aqueous lubrication treatment liquid and a method of cold plastic working metallic materials.
More particularly, this invention relates to an aqueous liquid used in a lubrication treatment for a cold plastic working (forging, tube drawing, wire drawing, etc.) of a steel, stainless steel, titanium-based metal, copper-based metal, aluminum-based metal material, etc. (hereinafter referred to as an aqueous lubrication treatment liquid) as well as a method of cold plastic working of a metallic material having a chemical conversion coating thereon with the aqueous lubrication treatment liquid.
2. Description of the Related Arts
As an aqueous lubrication treatment liquid currently used for the cold plastic working of a metallic material, liquids which comprise a solid lubricant, for example, molybdenum disulfide and graphite, at least one member selected from inorganic binders and organic binders, and a surfactant are known.
When a cold working is carried out at a relatively small reduction, a method in which an aqueous lubrication treatment liquid is brought directly into contact with a surface of a metallic material free from grease, followed by drying to form a solid lubricant film, is known.
In the case of a high reduction cold working, a method is employed of forming a solid lubricant film over a chemical conversion coating where a metallic material surface, after the formation of the chemical conversion coating, is brought into contact with an aqueous lubrication treatment liquid, followed by drying, or has a solid lubricant powder deposited thereon. Using a solid lubricant in a powder state, however, causes a problem of a deterioration of the working environment, and thus most preferably a lubricant in the form of an aqueous treatment liquid is used. In this case, however, a conventional aqueous lubricant treatment liquid has a drawback in that it causes rusting of the treated or formed metallic material when left to stand after the treatment or forming.
In the above cases, the currently used treatment agents cannot provide a stable and desired lubricity, which often results in the problems of seizing and galling.